Not sure what you did, but that doesn’t happen on my end. However, with all Genesis Themes (or any theme) the footer is the last div so of course if there is nothing pushing it down it will show up in the middle or wherever there is no content….which is normal. I don’t think there are too many ways to get it to stay all the way down without affecting other parts of the site.
I’m guessing you’re on a big screen of some sort? It shows up perfectly for me, but I’m on a laptop.